1. Field of the Invention
The present invention relates to a liquid detergent dispensing apparatus for use in washing machines, and more particularly, to a liquid detergent dispensing apparatus for automatically metering and dispensing variable quantities of detergent products during various phases or cycles of a washing sequence of a washing machine.
2. Description of the Related Art
Washing machines, particularly garment washing machines and dishwashing machines, are known which provide a drawer like or similar detergent container that is subdivided into plural separate compartments each adapted to contain pre-established, metered quantities of powder or liquid detergent products to be added during different phases or cycles of an on-going washing sequence. The container is in communication via a flexible conduit with the machine's wash tub or tank which is disposed below the container. Further, such detergent containers are generally provided with suitable control apparatus which is actuated by the machine's program/sequence control device. The machine is adapted to selectively apply an inlet water flow through a corresponding compartment of the detergent container during the various phases or cycles of a selected washing sequence to thereby flush off and convey into the machine's wash tub or tank a pre-established quantity of powder or liquid detergent contained in the compartment through which the inlet water flow was applied.
Washing machines are also known which include at least one storage reservoir that is capable of containing a sufficient supply of a liquid detergent to permit several washing sequences to be carried out, in contrast to the previously described detergent container which is adapted for carrying out only a single washing sequence at a time. The storage reservoir is provided in communication with the machine's was tub or tank and includes electro-magnetic shut-off valves or other suitable control devices that are actuated to open or close responsive to the machine's program/sequence control device. Such a reservoir is further associated with a known dispenser which is adapted to allow pre-established, constant quantities of liquid detergent to be added to the wash tub or tank of the machine during the pre-wash and wash phases of the washing sequence to be carried out by the machine, together with the necessary water inflow amounts of the respective wash phases.
Although the above-described known dispensers and washing machines are certainly capable of operating in a satisfactory and reliable manner, such dispensers and washing machines have a significant drawback in that it is necessary to provide program/sequence control devices that are specially designed and to identify the various pre-wash, soak and wash phases of the corresponding selected washing sequence, to thereby enable command of the appropriate quantity of liquid detergent to be selectively added to the wash tub or tank during each of the phases. A further drawback in such known dispensers and washing machines is that such are adapted to add only pre-defined, fixed quantities of liquid detergent, regardless of the actual amount of the wash load (i.e. garments or dishes) existing in the wash tub or tank. As such, optimum consumption of the liquid detergents cannot be realized, and as an additional consequence, consumption of the electric energy necessary to heat the resulting wash liquid solutions is relatively increased.